Children of her type contrive the purest philosophies. Ada had worked out her own little system. Hardly a week had elapsed since Vans arrival when he was found worthy of being initiated in her web of wisdom. An individuals life consisted of certain classified things: real things which were unfrequent and priceless, simply things which formed the routine stuff of life; and ghost things, also called fogs, such as fever, toothache, dreadful disappointments, and death. Three or more things occurring at the same time formed a tower, or, if they came in immediate succession, they made a bridge. Real towers and real bridges were the joys of life, and when the towers came in a series, one experienced supreme rapture; it almost never happened, though. In some circumstances, in a certain light, a neutral thing might look or even actually become real or else, conversely, it might coagulate into a fetid fog. When the joy and the joyless happened to be intermixed, simultaneo